In this paper, ZnO/Nb2O5 core/shell nanorod arrays were synthesized and used as photoanodes for dye- sensitized solar cells (DSSCs). We first synthesized ZnO nanorod array on fluorine-doped tin oxide (FTO) glasses...In this paper, ZnO/Nb2O5 core/shell nanorod arrays were synthesized and used as photoanodes for dye- sensitized solar cells (DSSCs). We first synthesized ZnO nanorod array on fluorine-doped tin oxide (FTO) glasses by a hydrothermal method, and then ZnO/Nb2O5 core/shell nanorod array was directly obtained via solvothermal reaction in NbCl5 solution. The scanning electron micro- scope (SEM) and transmission electron microscope (TEM) images revealed that the ZnO nanorods were uniformly wrapped by Nb2O5 shell layers with a thickness of 30-40 nm. Photovoltaic characterization showed that the device based on ZnO/Nb2O5 core/shell nanorod photoanode exhibited an improved efficiency of 1.995%, which was much higher than the efficiency of 0.856% for the DSSC based on bare ZnO nanorod photoanode. This proved that the photovoltaic performance of ZnO nanorods could be improved by wrapping with Nb2O5 shells.展开更多
The microwave dielectric properties and microstructure of BaTi4.3ZnyO9.6+y +0.02 mol% SnO2+0.01 mol% MnCO3+x mol% Nb2O5(x=0-0.05, y=0-0.08) system ceramics were studied as a function of the amount of ZnO and Nb2...The microwave dielectric properties and microstructure of BaTi4.3ZnyO9.6+y +0.02 mol% SnO2+0.01 mol% MnCO3+x mol% Nb2O5(x=0-0.05, y=0-0.08) system ceramics were studied as a function of the amount of ZnO and Nb2O5 doped. Addition of (y=0-0.05) ZnO and (x=0-0.025) Nb2O5 enhanced the reactivity and decreased the sintering temperature effectively. It also increased the dielectric constant ε r and quality factor Q(=1/tan 8) of the system due to the substitution of Ti^4+ ions with incorporating Zn^2+and Nb^5+ ions, which was analyzed by the reaction ZnO+Nb2O5+ 3 TiTxTi →ZnTi+ 2NbTi+3TiO2. When the system doped with (y=0.05) ZnO and (x=0.025) Nb205 were sintered at 1 160 ℃ for 6 h, the εr. Qf0 value and rfwere 36.5, 42 000 GHz, and+1.8 ppm/℃, respectively, at 5 GHz.展开更多
采用了固相反应法制备了(Bi1.9Li0.1)(Zn2/3Nb4/3-x Al x)O7介质陶瓷。研究了Li+替代Bi3+,Al3+替代Nb5+对Bi2(Zn1/3Nb2/3)2O7陶瓷烧结特性、相结构及介电性能的影响。结果表明:Li-Al共掺能显著降低BZN烧结温度,由1000℃降至920℃,能改...采用了固相反应法制备了(Bi1.9Li0.1)(Zn2/3Nb4/3-x Al x)O7介质陶瓷。研究了Li+替代Bi3+,Al3+替代Nb5+对Bi2(Zn1/3Nb2/3)2O7陶瓷烧结特性、相结构及介电性能的影响。结果表明:Li-Al共掺能显著降低BZN烧结温度,由1000℃降至920℃,能改善介电性能,并对介电常数温度系数具有调节作用。当Li+掺杂量为0.1 mol,Al3+掺杂量为0.2 mol时,在920℃温度烧结2 h获得最佳性能:εr=75.42,tgδ=1.67×10-3,αc=29.1×10-6。展开更多
Niobium doped Zincoxide nanoparticles has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, IR Spectroscopy, SEM, XRD, ICPMS and EDAX data. The UV-Visible spectroscopy resul...Niobium doped Zincoxide nanoparticles has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, IR Spectroscopy, SEM, XRD, ICPMS and EDAX data. The UV-Visible spectroscopy result reveals that the band gap energy of ZnO/Nb2O5 nanoparticles to be 3.8 eV. The XRD results show that the crystallite size is to be 31.9 nm. The ICPMS data indicate the presence of 3,3461,328 counts of 93 Nb and 577,906,390 counts of 66 Zn. An improvement in the photocatalytic degradation of Indigocarmine dye (IC) in comparison to commercially available pure ZnO was observed. The photodegradation efficiency for ZnO/Nb2O5 and ZnO were found to be 97.4% and 52.1% respectively. The enhancement in photocatalytic activity of ZnO/ Nb2O5 was ascribed to the extended light absorption range and suppression of electron hole pair recombination upon Nb loading. The antibacterial activity of ZnO/Nb2O5 nanoparticles was investigated. These particles were shown to have an effective bactericide.展开更多
文摘In this paper, ZnO/Nb2O5 core/shell nanorod arrays were synthesized and used as photoanodes for dye- sensitized solar cells (DSSCs). We first synthesized ZnO nanorod array on fluorine-doped tin oxide (FTO) glasses by a hydrothermal method, and then ZnO/Nb2O5 core/shell nanorod array was directly obtained via solvothermal reaction in NbCl5 solution. The scanning electron micro- scope (SEM) and transmission electron microscope (TEM) images revealed that the ZnO nanorods were uniformly wrapped by Nb2O5 shell layers with a thickness of 30-40 nm. Photovoltaic characterization showed that the device based on ZnO/Nb2O5 core/shell nanorod photoanode exhibited an improved efficiency of 1.995%, which was much higher than the efficiency of 0.856% for the DSSC based on bare ZnO nanorod photoanode. This proved that the photovoltaic performance of ZnO nanorods could be improved by wrapping with Nb2O5 shells.
基金the Natural Science Foundation of Tianjin (No. 06YFJMJC01000)
文摘The microwave dielectric properties and microstructure of BaTi4.3ZnyO9.6+y +0.02 mol% SnO2+0.01 mol% MnCO3+x mol% Nb2O5(x=0-0.05, y=0-0.08) system ceramics were studied as a function of the amount of ZnO and Nb2O5 doped. Addition of (y=0-0.05) ZnO and (x=0-0.025) Nb2O5 enhanced the reactivity and decreased the sintering temperature effectively. It also increased the dielectric constant ε r and quality factor Q(=1/tan 8) of the system due to the substitution of Ti^4+ ions with incorporating Zn^2+and Nb^5+ ions, which was analyzed by the reaction ZnO+Nb2O5+ 3 TiTxTi →ZnTi+ 2NbTi+3TiO2. When the system doped with (y=0.05) ZnO and (x=0.025) Nb205 were sintered at 1 160 ℃ for 6 h, the εr. Qf0 value and rfwere 36.5, 42 000 GHz, and+1.8 ppm/℃, respectively, at 5 GHz.
文摘Niobium doped Zincoxide nanoparticles has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, IR Spectroscopy, SEM, XRD, ICPMS and EDAX data. The UV-Visible spectroscopy result reveals that the band gap energy of ZnO/Nb2O5 nanoparticles to be 3.8 eV. The XRD results show that the crystallite size is to be 31.9 nm. The ICPMS data indicate the presence of 3,3461,328 counts of 93 Nb and 577,906,390 counts of 66 Zn. An improvement in the photocatalytic degradation of Indigocarmine dye (IC) in comparison to commercially available pure ZnO was observed. The photodegradation efficiency for ZnO/Nb2O5 and ZnO were found to be 97.4% and 52.1% respectively. The enhancement in photocatalytic activity of ZnO/ Nb2O5 was ascribed to the extended light absorption range and suppression of electron hole pair recombination upon Nb loading. The antibacterial activity of ZnO/Nb2O5 nanoparticles was investigated. These particles were shown to have an effective bactericide.